#!/bin/bash
set -e

#================================================================================================================#
# 功能：用于更新阿里云域名IP，实现DDNS功能
#
# 在 http://www.gebi1.com/forum.php?mod=viewthread&tid=287344&page=1&_dsign=8f94f74c 提供的脚本文件基础上修改的。
# ghui, modified 12/2/2019
# 在 N1 debian Buster with Armbian Linux 5.3.0-aml-g12 手动执行/定时任务(crontab)执行测试通过
#================================================================================================================#
#
# 使用方法：
#
# 方法1. 外部参数
# 修改源码，将对应参数 修改为$1,$2,$3,$4,$5,$6 
# aliddns.sh <aliddns_ak> <aliddns_sk> <aliddns_subdomain> <aliddns_domain> <aliddns_iptype> <aliddns_ttl>
# 示例（A 代表 IPv4，AAAA 代表 IPv6）: 
# 执行：aliddns.sh "xxxx" "xxx" "test" "mydomain.site" "A" 600
# 执行：aliddns.sh "xxxx" "xxx" "test" "mydomain.site" "AAAA" 600
#
# 方法2. 内部参数
# 修改源码，将$1,$2,$3,$4,$5,$6 替换为对应参数
# 
# 示例: 
# aliddns_ak="xxxx"
# aliddns_sk="xxx"
# aliddns_subdomain="test"
# aliddns_domain="mydomain.site"
# aliddns_iptype="A"
# aliddns_ttl=600 
# 执行：aliddns.sh
#
#================================================================================================================#

#--------------------------------------------------------------
# 参数
#
# (*)阿里云 AccessKeyId
aliddns_ak=LTAI5tBvYdMumm5TrZhxL5Sj
# (*)阿里云 AccessKeySecret
aliddns_sk=1eB9KbVfcyAJ1vMPLjzHRpGRg9TSX0


# (*)域名：test.mydomain.com 
aliddns_subdomain=openwrt #'test'
aliddns_domain=hflxhn.com #'mydomain.com'

# (*)ip地址类型：'A' 或 'AAAA'，代表ipv4 和 ipv6
aliddns_iptype=AAAA # 'A' 或 'AAAA'，代表ipv4 和 ipv6

# TTL 默认10分钟 = 600秒 
aliddns_ttl=600 #"600"

#--------------------------------------------------------------


# --------------------------------------------------------------------------------------------------
# 函数
#
# 输出分割行
function line() {
    echo -e "\033[33m#################### ${1} ##################\033[0m"
}

# 命令检查
function check() {
    if [[ $? == 0 ]]; then
        echo -e "\033[32m${1} --------> success\033[0m";
    else
        echo -e "\033[31m${1} --------> fail\033[0m"; exit 0;
    fi
}

# 输出一些信息
function output() {
    echo -e "\033[32m${1}\033[0m";
}

# 获取 ipv4 地址
function getMachineIPv4() {
    echo $(/usr/bin/wget -qO- -t1 -T2 http://ip.3322.net)
}

# 获取 ipv6 地址
function getMachineIPv6() {
    ipv6=$(ip addr | grep "inet6.*global" | grep -v "deprecated" | awk '{print $2}' | awk -F"/" '{print $1}' | sed -n '1,1p')
    echo $ipv6
}

# 获取当前映射的 ip
function getDDNSIP() {
    current_ip=$(nslookup -query=$aliddns_iptype $aliddns_name | grep "Address" | grep -v "#53" | awk '{print $2}')
    echo $current_ip
}

# url 编码
function urlencode() {
    # urlencode <string>
    out=""
    while read -n1 c
    do
        case $c in
            [a-zA-Z0-9._-]) out="$out$c" ;;
            *) out="$out`printf '%%%02X' "'$c"`" ;;
        esac
    done
    echo -n $out
}

function enc() {
    echo -n "$1" | urlencode
}

function sendRequest() {
    local args="AccessKeyId=$aliddns_ak&Action=$1&Format=json&$2&Version=2015-01-09"
    local hash=$(echo -n "GET&%2F&$(enc "$args")" | openssl dgst -sha1 -hmac "$aliddns_sk&" -binary | openssl base64)
    curl -s "http://alidns.aliyuncs.com/?$args&Signature=$(enc "$hash")"
}

function getRecordid() {
    grep -Eo '"RecordId":"[0-9]+"' | cut -d':' -f2 | tr -d '"'
}

function queryRecordid() {
    sendRequest "DescribeSubDomainRecords" "SignatureMethod=HMAC-SHA1&SignatureNonce=$timestamp&SignatureVersion=1.0&SubDomain=$aliddns_name&Timestamp=$timestamp&Type=$aliddns_iptype"
}

function updateRecord() {
    sendRequest "UpdateDomainRecord" "RR=$aliddns_subdomain&RecordId=$1&SignatureMethod=HMAC-SHA1&SignatureNonce=$timestamp&SignatureVersion=1.0&TTL=$aliddns_ttl&Timestamp=$timestamp&Type=$aliddns_iptype&Value=$(enc $machine_ip)"
}

function addRecord() {
    sendRequest "AddDomainRecord&DomainName=$aliddns_domain" "RR=$aliddns_subdomain&SignatureMethod=HMAC-SHA1&SignatureNonce=$timestamp&SignatureVersion=1.0&TTL=$aliddns_ttl&Timestamp=$timestamp&Type=$aliddns_iptype&Value=$(enc $machine_ip)"
}
# --------------------------------------------------------------------------------------------------


machine_ip=""
ddns_ip=""
aliddns_record_id=""

if [[ "$aliddns_subdomain" = "@" ]]; then
    aliddns_name=$aliddns_domain
else
    aliddns_name=$aliddns_subdomain.$aliddns_domain
fi

line "`date`"
output "domain name: $aliddns_name"

if [[ "$aliddns_iptype" = 'A' ]]; then
    machine_ip=$(getMachineIPv4) && output "ddns is IPv4: ${machine_ip}"
    aliddns_record_id=$aliddnsipv4_record_id
else
    machine_ip=$(getMachineIPv6) && output "ddns is IPv6: ${machine_ip}"
    aliddns_record_id=$aliddnsipv6_record_id
fi

ddns_ip=$(getDDNSIP) && output "ddns_ip: $ddns_ip"


if [[ ${machine_ip} != "" ]]; then
    output "machine_ip is empty!"; exit 0;
fi

if [[ ${machine_ip} == ${ddns_ip} ]]; then
    output "No need to update ddns mapping"
fi



# echo "start update..."

# timestamp=`date -u "+%Y-%m-%dT%H%%3A%M%%3A%SZ"`

# if [ "$aliddns_record_id" = "" ]
# then
#     aliddns_record_id=`query_recordid | get_recordid`
#     echo "----------------" $aliddns_record_id "\n"
    
#     if [ "$aliddns_iptype" = 'A' ]
#     then
#         aliddnsipv4_record_id=$aliddns_record_id
#     else
#         aliddnsipv6_record_id=$aliddns_record_id
#     fi
# fi

# #add support */%2A and @/%40 record
# if [ "$aliddns_record_id" = "" ]
# then
#     echo "add record starting"

#     aliddns_record_id=`add_record | get_recordid`

#     if [ "$aliddns_record_id" = "" ]
#     then
#         echo "aliddns_record_id is empty. \n"
#     else
#         if [ "$aliddns_iptype" = 'A' ]
#         then
#             aliddnsipv4_record_id=$aliddns_record_id
#         else
#             aliddnsipv6_record_id=$aliddns_record_id
#         fi

#         echo "added record $aliddns_record_id \n"
#     fi
# else
#     echo "update record starting"
#     update_record $aliddns_record_id
#     echo "updated record $aliddns_record_id \n"
# fi


